The paraphysis and pineal region of the garter snake

B. W. Kunkel
1915 The Anatomical Record  
FORTY-ONE FIGURES The pineal region of the vertebrates has been studied by a large number of investigators whose interest has been directed especially to the parietal organ and epiphysis, the significance and functions of which are still so problematical. On account of the relatively high state of development of the parietal organ in Sphenodon and many lizards, the reptiles have received special attention and the papers of Warren ('11) on the development of the pineal region in the lizard and
more » ... in the lizard and turtle, Dendy ('99) on Sphenodon, and Voeltzkow ('03) on the crocodilian furnish rather complete pictures of the development of the region in each one of these groups. The snakes have received very little attention from this point of view and are only very imperfectly known. It was for the purpose of filling up certain serious gaps in our knowledge regarding this group that the present study was undertaken. The literature dealing with the pineal region in snakes is very restricted. The earliest reference to this region is Hoffmann's ('85). In describing briefly the pineal region in Tropidonotus natrix, he called attention to a thickening of the roof of the brain at the boundary between t,he telencephalon and diencephalon. He offered no suggestion as to its significance but there can be little doubt that it was the anlage of the paraphysis which he saw. Hanitsch ('88) in a paper which I have not been able to see for myself, describes according to Leydig ('97) an organ which he supposed to be a well defined parietal eye in an embryo Vipera berus. He described the eye as provided with a lens in 607 TXE ANATOMICAL RECORD, VOL. 9, N O . 6
doi:10.1002/ar.1090090803 fatcat:e5efr3hx25hkjeros6eaamdepm